US2815859A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Concentration of phosphatic material
Assignee: SMITH DOUGLASS CO Inc
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Filing: 1954-10-15
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Granted: 1957-12-10
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Expires: 1974-10-15
Abstract
No abstract record available.
Inventors
- 👤 Clinton A Hollingsworth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 11:13
CPC Classifications
B; B03; B03D; B03D1/00; B03D1/02; B03D1/021
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
51 words
THE METHOD OF SEPARATING SILICA FROM AN UNSIZED SILICA-CONTAINING PHOSPHATE PRODUCT WHICH COMPRISES SUBJECTING THE DESLIMED AND UNSIZED PHOSPHATE PRODUCT TO A FIRST ROUGHER STEP OF PNEUMATIC FROTH FLOTATION IN THE PRESENCE OF A CATIONIC COLLECTING FLOTATION AGENT AND THE THE COURSE OF WHICH A SILICA FROTH AND A ROUGHER PHOSPHATE
Claim 2
Independent Claim
51 words
THE METHOD OF SEPARATING SILICA FROM AN UNSIZED SILICA-CONTAINING PHOSPHATE PRODUCT WHICH COMPRISES SUBJECTING THE DESLIMED AND UNSIZED PHOSPHATE PRODUCT TO A FIRST ROUGHER STEP OF PNEUMATIC FROTH FLOTATION IN THE PRESENCE OF A CATIONIC COLLECTING FLOTATION AGENT AND THE THE COURSE OF WHICH A SILICA FROTH AND A ROUGHER PHOSPHATE
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-12-09 | 1961-06-10 | 1961-12-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-12-09 | 1965-06-10 | 1965-12-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-12-09 | 1969-06-10 | 1969-12-10 | $7700.00 | Window Closed / Lapsed |